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Biology Core
Cells Study Guide
1. What are the 3 parts of the cell theory?
i)
ii)
iii)
All life is made up of cells.
Cells are the basic unit of life.
All cells come from pre-existing cells.
2. Name and describe 1 piece of evidence for the cell theory.
i)
ii)
iii)
All life is made up of cells.
 Living organisms, when viewed under a microscope, are seen as
clusters of cells.
Cells are the basic unit of life.
 Organelles cannot perform the basic functions of life by itself.
All cells come from pre-existing cells.
 Robert Hooke disproved spontaneous generation of cells when he
first discovered them in cork under a microscope. Also, cells
reproduce by mitosis, or cell division.
3. What is a single cell organism called?
Unicellular organism.
4. Do the organisms in 3 perform all functions of life?
Yes.
5. What are those functions of life?
Movement
Reproduction
Sensitivity
Homeostasis
Growth
Nutrition
6. Compare the size of a cell to the thickness of a molecule, a cell membrane, a
virus, a bacteria and organelles.
Molecule:
Membrane:
Virus:
1nm
10nm
100nm
Bacteria:
Organelles:
Cells:
1µm
10µm
100µm
7. Describe how to calculate the magnification of a cell under the microscope.
Size of diagram in μm
Actual size of cell in μm
8. What are scale bars and how are they useful?
A scale bar is a line in a micrograph to help show the actual size of the structures
in proportion.
9. Describe why cells cannot grow too large.
When cells grow, the surface are, which is in charge of the rate of enter/exit of
materials in the cell, grows at a slower rate compared to the volume, which
controls the rate materials are used/produced. Because of this, materials cannot
get quickly enough inside and outside of the cell, forcing the cell to undergo
mitosis (cell division) to allow a balanced flow of materials.
10. Instead, what do they do?
They undergo mitosis (cell division) to prevent from dying.
11. What are emergent properties and what do they have to do with a cell?
Emergent properties me4ans that the whole is greater than the sum of the parts,
meaning that cells work more efficiently as a team rather than individually.
12. Do all cells have the same DNA? If so, why are they different?
Cells have the same DNA. However, different cells express different parts of the
DNA based on their functions. This is called differentiation.
13. What are stem cells and why are they important?
Stem cells are cells that have the ability to self-renew by mitosis and differentiate.
They are important because current research suggests that these cells can be used
to replace damaged or dead cells that do not undergo cell division, such as bone
marrow and insulation tissue of damaged neurons.
14. Describe the therapeutic use of stem cells. What is your opinion and why?
A therapeutic us of stem cells could be to combat a cancer called leukemia, which
is when bone marrow cells divide too quickly, producing too many white blood
cells.
1. Blood is drained out of umbilical cord from placenta after childbirth.
2. Red blood cells are removed from cord blood; remaining fluid tested for
abnormalities, disease-causing organisms and tissue type is identified.
3. Cord blood is stored in a special liquid nitrogen blood bank.
4. Patient’s tissue type matched with corresponding cord blood.
5. Patient given chemotherapy drugs to kill both harmful and good bone marrow
cells.
6. Cord blood is then thawed and inserted into patient’s system so stem cells can
differentiate into new bone marrow cells.
15. What is a prokaryote?
Cells that do not have a nucleus and divide by binary fission.
16. Draw and label a prokaryote cell with the following: cell wall, plasma
membrane, cytoplasm, pili, flagella, ribosomes, and nucleoid.
17. Describe the function o f each of the parts listed in #16.
Cell wall
Plasma membrane
Cytoplasm
Pili
Flagella
Ribosomes
Nucleoid
Provides support and shape
“Gatekeeper” of the cell, controls enter/exit of materials
inside cell
Contains enzymes for chemical reactions and the nucleoid
Hairlike extensions that pulls cells together and exchanges
DNA
Whiplike tail for motion
Granular structures that synthesize (create) proteins
Part of the cytoplasm that contains “naked” (exposed)
DNA (not in chromosomes)
18. Describe how prokaryotic cells divide.
DNA replicates, moves to the opposite sides of the cell, and the cell divides.
19. Describe the function of the following: rough ER, lysozomes, Golgi
apparatus, mitochondria, and nucleus.
RER
Lysozomes
Golgi apparatus
Mitochondria
Nucleus
Flattened sacs with a thin membrane that controls
transport of materials within the cells, contains ribosomes
Sacs with digestive enzymes to destroy worn out
organelles
Flattened sacs for processing and transport of materials
outside the cell
Folded membrane called cristae; cell respiration occurs
here (02 + Glucose = CO2 + ATP + H2O)
Cell structure containing DNA; surrounded by a nuclear
envelope and has a nucleolus, controls functions of
organelles
20. Compare and contrast prokaryotic and eukaryotic cells.
Feature:
Type of genetic
material
Location of genetic
material
Mitochondria
Ribosomes
Internal membranes
Prokaryotic Cells
Naked loop of DNA in
cytoplasm
Cytoplasm
Eukaryotic Cells
DNA located in chromosomes
None present
Small sized – 70S
Few or none present
Always present
Large sized – 80S
Many internal membranes contained
in the cytoplasm
In the cytoplasm, in the nucleoid
21. Describe 3 differences between plant and animal cells.
Feature:
Cell wall
Chloroplasts
Polysaccharides
Plant Cell
Present
Present
Excess glucose stored as
starch
Animal Cell
Not present
Not present
Excess glucose stored as
glycogen
22. Describe 2 roles of extracellular components.
In plants: Cellulose provides fixed shape, prevents excess water uptake, and holds
plant up against gravity.
In animals: Glycoprotein forms extracellular matrix for support, adhesion, and
movement.